This invention relates generally to toggle switch boot seals of types disclosed, for example, in my prior U.S. Pat. Nos. 3,175,833 of Mar. 3, 1965; and 3,420,119 of Jan. 7, 1969.
In prior art constructions, it has been a primary purpose to achieve a good seal while at the same time allowing easy flexing with the toggle lever. This is accomplished by reducing the back-torque from the seal, and thereby avoiding the overriding detenting of the toggle switch. In the seals disclosed in the above-mentioned patents, utilization was made of thin-walled sections which easily stretch and flex, in order to allow the toggle lever to move from one extreme position to the other.
When these thinner-walled sections are used, however, the permissable internal pressures are reduced, since thinner walls have a tendency to balloon. It is possible to overcome the ballooning effect by building a rib or thicker section into the thin wall. This rib performs in a manner somewhat like a barrel hoop to reinforce the thin section against the expanding action of the internal pressure. The disadvantage of the rib becomes apparent when external pressures are applied to the sealing system, for in the latter case, the reinforcing rib is driven inwardly and takes a position which inhibits the action of the toggle. Further, in previous constructions, the dilation caused by internal pressure has tended to loosen the grip of the seal around the neck of the lever, which, in the case of a sleeve-type seal has permitted leakage.